Method for producing mixed filaments

ABSTRACT

Synthetic fibers having natural fiber-like touch, gloss, texture and appearance are produced by spinning a polyester and a polyamide through a common spinneret simultaneously to form mixed filaments consisting of multisegment-filaments, in each of which the polyester is divided by the polyamide into at least 3 segments, and polyester single component filaments, drawing the mixed filaments and then subjecting the drawn mixed filaments to a false twisting to fibrillate the multisegment filaments.

United States Patent Matsui et al.

[ Dec. 10, 1974 METHOD FOR PRODUCING MIXED FILAMENTS Inventors: MasaoMatsui; Susumu Tokura;

,Ma a n m e aebe llq Osaka Japan Assignee: Kanebo, Ltd., Tokyo, JapanFiled: Feb. 13, 1973 Appl. No.: 332,068

Foreign Application Priority Data Feb. 24, 1972 Japan 47-19451 U.S. Cl264/103, 57/140, 264/147,

264/168, 264/171 Int. Cl D02g 1/20 Field ofSearch ..264/171,174; 161/175References Cited UNITED STATES PATENTS l/l969 Felix 264/103 12/1971Funahashi l 264/171 2/1972 Matsui et al. 264/174 3,672,802 6/1972 Matsuiet al. 264/171 3,705,226 12/1972 Okamoto et a1. 264/174 3,718,534 2/1972Okamoto et a1. 264/171 3,725,192 4/1973 Ando et a1 264/177 F FOREIGNPATENTS OR APPLICATIONS 2,117,076 11/1971 Germany 264/171 PrimaryExaminer-Jay H. W00 Attorney, Agent, or Firm-Woodhams, Blanchard andFlynn [5 7 ABSTRACT Synthetic fibers having natural fiber-like touch,gloss, texture and appearance are produced by spinning a polyester and apolyamide through a common spinneret simultaneously to form mixedfilaments consisting of multisegment-filaments, in each of which thepolyester is divided by the polyamide into at least 3 segments, andpolyester single component filaments, drawing the mixed filaments andthen subjecting the drawn mixed filaments to a false twisting tofibrillate the multisegment filaments.

10 Claims, 8 Drawing Figures F12 Haj F/GL/ METHOD FOR PRODUCING MIXEDFILAMENTS The present invention relates to a method for producing mixedfilaments consisting of polyester and polyamide, which have differentcross-sectional shapes.

Conventional polyester or polyamide fibers are excellent in dynamicproperties but the fineness and cross-sectional shape of each of thesingle component filaments are simple and therefore the touch, gloss,texture and appearance thereof are more simple than natural fibers.

In order to overcome this drawback, various attempts have beenheretofore made but satisfactory results have not been obtained. Forexample, attempts have been made to spin filaments having differentdeniers from a common spinneret. The smallest denier of the monofilamentobtained in this process is up to 1.5 denier, usually more than 2deniers considering the operability, and from such filaments, it isdifficult to obtain the desirable texture, touch and the like. Asfilaments provided with the natural fiber-like excellent properties, itis desirable to have a large number of filaments of non-circularcross-section of extremely fine denier (for example, about 0.5 denier),and in order to keep a moderate resiliency and excellent dynamicproperties, it is desired to have filaments having a denier of severaltimes as large as the extremely fine filaments.

Even if such filaments can be spun by the above described process, thefilaments of an extremely fine denier and the filaments having a largedenier are different in behavior in the spinning step (for example,solidification, speed, and the like), and it is difficult to find outthe drawing condition suitable for any filaments in the subsequentdrawing step, so that finally filaments poor in the dynamic property areformed.

The object of the present invention is to provide a novel method forreadily producing the filaments provided with both the preferableproperties of synthetic fibers and natural fibers.

The present invention consists in a method for producing mixed filaments(D), which comprises spinning a polyester and a polyamide through acommon spinneret simultaneously to form an intermediate mixed filamentproduct (C) consisting of multisegment filaments, in each of which thepolyester is divided in cross-section by the polyamide into at least 3segments, and (B) polyester monofilaments, so as to satisfy thefollowing definitions,

1. the ratio of the multisegment filaments (A) to the total mixedfilaments (C) is 40-70 percent by weight,

2. the ratio of polyamide in each of the multisegment filaments (A) isless than 40 percent by weight, preferably less than 30 percent byweight and the ratio of polyamide in the total mixed filament product(C) is less than 30 percent by weight, preferably less than 25 percentby weight,

3. the polyamide in each multisegment filament (A) forms thin layershaving an even thickness which diverge radially in the cross-section ofsaid multisegment filament (A), and

4. each polyester segment in the multisegment filament (A) is less thanI denier, preferably less than 0.7 denier and the polyester monofilament(B) is more than 2 deniers, preferably more than 3'deniers,

drawing the spun mixed filament product (C) and then subjecting thedrawn mixed filament product (C) to a false twisting to fibrillate themultisegment filaments (A) contained therein and, thereby produce mixedfilament product (D).

The term segment used herein means that portion constituting themultisegment filament, which substantially extends evenly along thelongitudinal direction of the filament. The term forming the thin layershaving an even thickness diverging radially" means a thin layerstructure extending in ,at least three directions radially from onepoint, such as the Y-shape as shown in FIG. 1, the X-shape as shown inFIG. 2, and the six branches as shown in FIG. 3. Such radial thin layerstructure can be easily formed as mentioned hereinafter and suchmultisegment filaments can be efficiently separated by a false twistingand easily fibrillated.

The inventors have already found that such multisegment filament(filaments having the cross-sections as shown in FIGS. 1 to 3) is usefulas proposed in Japanese Patent Application No. 29,925-1970. These fibersare very favorable on account of being similar to natural fibers in thetexture, touch and gloss, but the fibers are poor in other respects.Namely, these fibers are too soft for use in gentlemans suit cloth orladys thick suit cloth which requires a certain degree of resiliency,and are not suitable for them. If the fineness of the segment isenlarged (for example, 3 deniers) in order to overcome this drawback,the preferable properties as described above are lost.

The inventors have found that when the multisegment filaments polyestersingle component filaments are simultaneously spun, the features of theabove described multisegment filament are maintained and further amoderate resiliency can be obtained.

Namely, in order to attain the object of the present invention, theweight ratio of the multisegment filaments in the total mixed filamentssimultaneously spun is 40-70 percent by weight. When the ratio of themultisegment filaments is less than 40 percent by weight, the excellentnatural fiber-like properties cannot be obtained and when the rate ismore than percent by weight, the resulting fibers are too soft anddeficient in the dimensional stability. That is, the ratio of themultisegment filaments must be selected within the above range dependingupon the object.

Polyamide and polyester are different in their shrinkability, and ingeneral polyamide is greater in shrinkage than polyester, that is,polyamide has less dimensional stability than polyester. Of course, ifpolyester is drawn at a low temperature, the shrinkability increases andmay become the same as the shrinkability of polyamide, but yarn breakageoccurs in the drawing step, and the drawing becomes unstable. When themixed filaments composed of the multisegment filaments consisting ofpolyester and polyamide and the polyester single component filaments aredrawn under a condition suitable for the polyester, the multisegmentfilaments are more highly shrunk and cause loose filaments (floatingthread) and these filaments are not only entangled on the guide ortraveller in the drawing but also cause hindrance in theafter-treatments, such as false twisting, warp beaming, warping and thelike. Consequently, in order to solve this problem, the ratio ofpolyamide to the multisegment filament must be decreased. As the resultof various investigations, it has been found that the ratio of polyamidein the multisegment filaments must be less than 40 percent by weight,preferably less than 30 percent by weight and further the ratio ofpolyamide in the total mixed filaments must be less than 30 percent byweight, preferably less than 25 percent by weight.

In order to divide the polyester into at least 3 segments by thepolyamide and to make small the ratio of polyamide in the multisegmentfilaments as far as possible, it is most reasonable that the polyesterand the polyamide are bonded in such a state that the polyamide formsthin layers having a substantially even thickness which divergeradially, in the cross-section of each of the above describedmultisegment filaments.

The filaments having the cross-sections as shown in FIGS. 1 to 4 can beproduced while maintaining a very stable bonding form as explainedhereinafter. On the contrary, a filament as shown in FIG. 5, in which acomponent is divided with another component forming very uneven thinlayers, is liable to cause aggregation of polymer in the spinning and aslight variation of the melt viscosity of both the components influencesupon the bonded shape and it is difficult to produce such a filamenthaving a uniform cross-sectional structure along the longitudinaldirection and the'fibrillation of the resulting filament is not effectedefficiently.

In order to improve the fibrillation of the filamenet having such across-section, it is necessary to increase the rate of thin layercomponent, while in the filaments as shown in FIGS. 1 to 4 wherein afilament forming component is bonded by the radially diverged thinlayers having an even thickness, it is easy to decrease the ratio ofthin layer component to less than 30 percent by weight and even if theratio is reduced to about percent, it is possible to maintain an evencross-sectional structure along the longitudinal direction of thefilament. I

The larger the number of the polyester segments in each of themultisegment filaments, the higher is the advantage in view of thefibrillation, but when the number of segments is increased too much, theproduction is difficult and further it is difficult to divide thepolyester evenly with a small amount of polyamide. In general, thenumber of polyester segments in each of the multisegment filaments ispreferred to be 3-8, preferably 3-6.

The smallest polyester segment in the multisegment filament must be lessthan 1 denier. The extremely fine filaments obtained by fibrillation ofsuch a filament have desirable texture, appearance and gloss similar tonatural fibers. In general, the multisegment filaments composed ofpolyester segments having an even crosssection as shown in FIGS. 1 to 3are useful, but in some cases, the multisegment filament as shownin'FIG. 4, wherein the area and cros-sectional shape of the poly estersegments are different, is preferable, because various forms of fibrilscan be formed.

The polyester filaments spun simultaneously with the multisegmentfilaments serve to provide the moderate resiliency and excellent dynamicproperties, which are characteristics of synthetic fibers, to theresulting fibers and a relatively large fineness, that is more than 2deniers, usually about 3-10 deniers, is preferred.

The mixed filaments in which extremely fine fibril-- lated filaments andusual filaments (monofilament of 2-10 deniers) are fully entangled,develop an excellent effect. These mixed filaments can be obtained byproducing the multisegment filaments and single component filamentssimultaneously and when the separately produced filaments are mixed,both the filaments are not fully entangled. 1

For a better understanding of the invention, reference is made to theaccompanying drawings, wherein:

FIGS. 1 to 5 show embodiments of cross-sections of filaments;

FIG. 6 is a vertical cross-sectional view of spinneret which can producethemixed filaments of the present invention;

FIG. 7 is a cross-sectional view of the spinneret as shown in FIG. 6 inthe arrow direction on lines X-X'; and

FIG. 8 is a cross-sectional view of the spinneret as shown in FIG. 6 inthe arrow direction on lines Y-Y'.

The mixed fibers obtained by the method of the present invention can beproduced in a high evenness of the cross-sectional structure by arelatively simple apparatus.

Referring to FIG. 6, an inner spinneret plate is superposed on aspinneret plate 110.

A part of the melted polyester is extruded from inner orifices 5 througha supplying chamber 2 and a passage 3 and the melted polyamide isextruded from channels 8 through a supplying chamber 1, passage 6 and areservoir 7. Both the polymers are bonded at an inlet of a conduit 9 andspun from an orifice 111 through the conduit 9. On the-other hand, apart of the remaining polyester is spun from an orifice 111 through asupplying chamber 2, a passage 4 and a conduit 9. Part number 120 is asupporter.

FIG. 7 is a cross-sectional view of the spinneret as shown in FIG. 6 inan arrow direction on lines XX' and shows the bottom of the innerspinneret 100. The inner orifices 5 and the passages 4 are opened at theprojecting portion of the bottom of the inner spinneret plate 100corresponding to the spinning orifices 111 in the spinneret plate 110.The inner orifices 5 consist of four small holes. At the top face of theprojecting portion in the bottom of the inner spinneret plate where eachof the four small holes opens, channels 8 are provided between theoutlets of the adjacent small holes.

FIG. 8 is a cross-sectional view of the spinneret as shown in FIG. 6 inan arrow direction on lines YY' and shows the upper face of thespinneret plate provided with circular spinning orifices 111.

The spinneret as shown in FIGS. 6 to 8 provides the mixed filamentsconsisting of 3 multisegment filaments in which polyester is dividedwith four radially diverged polyamide thin layers into 4 segments and 3polyester monofilaments.

By using a non-circular cross-sectional spinning orifice, non-circularcross-sectional filament can be easily obtained. However, consideringthe operability, the cross-section of the filament is preferred to besubstantially circular. Furthermore if the numbers of the inner orifices5 and the channels 8 are varied, the multisegment filaments having thecross-section as shown in FIGS. 1, 3 and 4 can be easily obtained. Thedeniers of the multisegment filaments and the polyester single componentfilament may be either the same or different, but when both thefilaments have the same denier, thefilaments having improved dynamicproperties are apt to be obtained. The denier ratio of both thefilaments is preferred to be about /7-7/10. A given value of the denierratio of both the filaments can be obtained by selecting the diameter orlength of the orifice 111.

When the filaments obtained by the above described method are applied toa false twisting, the segments in the multisegment filaments areseparated into fibrils and the polyester single component filaments andthe fibrillated segments are fully entangled to form the desired mixedfilaments.

The term false twisting" used herein means that the filaments aretwisted and then partially untwisted. The false twisting includes ausual false twisting (abbreviated to as FT process) wherein twisting anduntwisting are effected continuously and a process wherein aftertwisting, twisting in the reverse direction is made (referred to asmulti-step process). ln general, FT process is preferred in view of theworking efficiency and therefore an explanation will be made withrespect to this process.

The object of the false twisting lies in fibrillation of themultisegment filament as mentioned above. The multisegment filament isreadily fibrillated and therefore 'it is not necessary to determine thenumber of twistings (when a spindle is used, rotation number ofspindle/yarn velocity) exactly as in the usual twisting.

For the object of the present invention, the number of twist (falsetwisting) necessary per meter of filament is 0.lX-l.5X, particularly0.5Xl.2X (provided that, X=270,000/d+60+800, d=denier of originalfiber).

in the same manner, the twisting may be effected at room temperature(for example, 20C) or by heating (for example, 190C) and the feed ratio(velocity of feed roller/velocity of delivery roller) may be 0.8-2.0.

The above explanation was made with respect to FT process but FT processmay be effected more than two times and further after the false twistingby FT process, a heat-setting and conventional twisting may be effected.

Then, an explanation will be made with respect to the multi-stepprocess.

This process may combine two steps of twisting-reverse twisting. threesteps oftwisting-heat settingrcverse twisting. four steps oftwisting-heat settin' g-reverse twisting-heat setting or may combinefurther many steps.

In this case. the number of twists for effecting fibrillation (usuallythe first step) is the same as in the above described FT process. Thenumber of twists in the reverse direction effected thereafter may be thesame as or different from the original number of twists but is preferredto be at least 50, preferably at least 70 percent of the original numberof twists. When the original number of twists is different from thenumber of reverse twists, the fibers are actually twisted and the numberof actual twists and the direction thereof can be selected dependingupon the object.

The false twisting effected in FT process may be carried out by aconventional false twisting machine provided with a false twistingportion consisting of a spindle between a feed roller and a deliveryroller and a heating portion consisting of an electric heater or may becarried out by providing a false twisting portion between a deliveryroller of a drawing apparatus and a winding up appartus to effect thedrawing and false twisting continuously.

As the false twisting portion, use may be made of conventional means,for example, a spindle a means for applying false twists to filamentsdirectly by contacting the filaments with a rotating roller, that is ameans for applying twists directly by a friction and air jet type meanswhich applies false twists to filaments by a rotating flow of compressedair.

As the heating portion, use may be made of conventional plate-shaped ortube-shaped heating elements but as mentioned above. Any heating elementmay not be used depending upon the purpose. In the multi-step process,conventional twisters (double twister, uptwister and the like) may beused. The heat-setting may be effected by the following means. That is,a bobbin wound with filaments is heated with steam or hot water or therunning filament is heated by a metal heater or a heater tube. By themethod of the present invention, various fibers can be obtained.

As polyesters to be used in the present invention, mention may be madeof polyethylene therephthalate, polyethylene oxybenzoate,polytetramethylene terephthalate, polydimethylcyclohexane terephthalate,polypivalolactone and copolyesters containing the components of thesepolyesters.

As polyamides to be used in the present invention, mention maybe made ofnylon 6, nylon 66, nylon l l, polymethaxylene adipamide and copolymerscontaining the components of these polyamides.

The combination of polyester and polyamide to be used in the presentinvention can be selected optionally depending upon the object but whenhighly crimped filaments are to be obtained by applying false twists, itis preferred to combine polyester and polyamide, which are equal in theappropriate false twisting conditions, for example, a combination ofpolyethylene terephthalate and nylon 66.

The following examples are given for the purpose of illustration of thisinvention and are not intended as limitations thereof.

EXAMPLE 1 By using the spinneret as shown in FIG. 6, provided that 18orifices 111 are arranged in a circumference of a spinneret plate 110and 9 groups of inner orificies 5 and channels 8, and 9 passages 4 areopened on the bottom of the inner spinneret alternately corresponding tothe orifices 111, polyethylene terephthalate (PET) having an intrinsicviscosity of 0.71 in ochlorophenol solution at 30C and polyhexamethyleneadipamide (nylon 66) having an intrinsic viscosity of 1.05 in metacresolat 30C are melted separately and the melted PET and the melted nylon 66are supplied to a supplying chamber 2 and a supplying chamber 1 in aweight ratio 7/1 by metering pump respectively. The temperature of thespinneret is maintained at 290C and both the melted polymers are spunfrom circular orifices, each having a diameter of 0.25 mm, and cooled inair and the spun filaments are wound up at a velocity of 700 m/min,while oiling, drawn to 3.6 times on a drawing pin at C, and wound upwhile contacting with a metal plate at C for about 0.l sec. to obtaindrawn yarns of 75 denier/l8 filament, which is referred to as yarn F Theyarn F, is composed of 9 polyester single component filaments and 9multisegment filaments having the cross-section as shown in FIG. 2wherein PET is divided bythin layers of nylon 66 into 4 segments and 4segments are uniformly dispersed (conjugate ratio of PET/nylon 66 being3/1).

For comparison, the multisegment filament and the polyester singlecomponent filament are separately spun and drawn.

Namely, by using a spinneret as shown in FIG. 6, provided that 18orifices 111 are arranged on a spinneret plate 110 and 18 groups ofinner orifices and channels 8 corresponding to said orifices 111 areprovided on the inner spinneret plate 100, PET and nylon 66 are spun anddrawn in the same manner as in the production of yarn F provided thatthe feed ratio of PET/nylon 66 is 3/1 by weight, whereby multisegmentfilament of 75 denier/18 filamentare obtained, which is referred to'asyarn F Separately, PET is spun in a conventional process to form PETfilaments having 75 denier/l8 filament, which is referred to as yarn FYarns F F and F are false twisted and then fed into a metal tube heaterhaving an inner diameter of 3 mm and a length of 50 cm heated at 215Cand taken out at a rate of 60 m/min through a spindle rotating at200,000 rpm and wound up at a rate of 55 m/min.

After the false twisting, the yarns F and F are com- 'pletelyfibrillated and in the yarn F, the fibrillated segments and thepolyester single component filaments are thoroughly entangled anddispersed homogeneously, each of the above false twisted yarns isS-twisted and Z-twisted and these twisted yarns are mixed and thenformed into a plain knitted goods by a circular knitting machine ofgauge and these knitted goods are refined, dyed and steam set to formsuit cloths.

The resulting suit cloths are estimated and the results are shown in thefollowing Table l.

Table l Shape Yarn Bulkiness Resiliency Softness retaining property F,Present Invention o o o o F, Comparative A X o X F: Comparative A o X oEXAMPLE 2 The mixed filaments are produced in substantially the samemanner as in the yarn F, in Example 1, provided that the feed ratio ofPET/nylon 66 is varied to 3/1, 5/1, 7/1 and 9/1. When the feed ratio ofPET/nylon 66 is 3/l,'the conjugate ratio of PET/nylon 66 in themultisegmentfilament is substantially 111. When the feed ratios are 5/1,7/1 and 9/1, the conjugate ratios are substantially 2/1, 3/1 and 4/1,respectively. When the conjugate ratio of PET/nylon 66 of multisegmentfilament is 1]] and 2/1, that is when the rate of polyamide in themultisegment filament is 50 percent and 33 percent, the yarns wound onbobbins after drawing float loose filaments and cause hindrance in thefollowing false twisting step.

On the other hand, when the conjugate ratio is 3/1, that is when therate of polyamide in the multisegment filament is 25 percent, the amountof the loose filaments is small and there is no hindrance in thefollowing step. In the yarn ofa conjugate ratio of 4/1 wherein the rateof polyamide in the multisegment filament is 20 percent, there is noloose filament.

EXAMPLE 3 epolycaproamide (nylon 6, intrinsic viscosity in themetacresol solution at 30C being 1.1) and PET are spun and drawn in thesame manner as described in Example l in a feed ratio of PET/nylon 6being 9/1 to obtain yarn P of 75 denier/18 filament. The resulting yarnF is false twisted. Thethus treated yarns are fed at a rate of 60 m/minwithout using a heater and taken out at a rate of 60 m/min through afalse twisting spindle rotating at 1,900,000 rpm and wound up at a rateof 61.2 m/min.

The multisegment filaments in the yarn F after the false twisting arefibrillated. The yarn F after the false twisting is not substantiallycrimped and is flexible and has a moderate resiliency and showssilk-like gloss.

What is claimed is:

1. A method for producing a yarn consisting ofa mixture of (A)fibrillated multisegment composite filaments consisting of polyester andpolyamide and (B) polyester monofilaments, said polyamide being selectedfrom the group consisting of polyhexamethylene adipamide, polycaproamideand copolyamides thereof, said polyester being selected from the groupconsisting of polyetheylene terphthalate and copolyesters thereof whichcomprises simultaneously and separately spinning through a commonspinneret (1) monofilaments of polyester having a denier of more than 2to form component (B) and (2) composite filaments of polyester andpolyamide in which the polyester of each composite filament is dividedinto at least three separate segments by thin interesecting polyamidelayers having a substantially uniform thickness throughout their lengthand which extend radially and diverege in a direction away from theirintersection toward the periphery of said composite filament, saidpolyester segments having a denier of less than 1, said compositefilaments being from 40 to percent by weight based on the sum of theweights of said monofilaments and composite filaments, said polyamidbeing less than 40 percent by weight based on the weight of saidcomposite filaments and said polyamide being less than 30 percent byweight based on the sum of the weights of said monofilaments andcomposite filaments,

combining the monofilaments and composite filaments, drawing thecombined filaments and then false twisting the combined filaments tofibrillate said composite filaments whereby to form a yarn in which thefibrillated segments of said composite filaments and said polyesteremonofilaments are entangled and are homogeneously dispersed. 2. A methodas claimed in claim 1, wherein said polyamide in the total mixedfilaments is less than 25 percent by weight.

7. A method as claimed in claim 1, wherein the polyester is polyethyleneterephthalate.

8. A method as claimed in claim 1, wherein the polyamide ispolyhexamethylene adipamide.

9. A method as claimed in claim 1, wherein the polyamide ise-polycaproamide.

10. A method according to claim 1, in which the feed ratio of polyesterto polyamide fed to said spinneret is 7/1 or less and the conjugationratio of polyester to polyamide in said composite filament is 3/1 orless.

1. A METHOD FOR PRODUCING A YARN CONSISTING OF A MIXTURE OF (A)FIBRILLATED MULTTSEGMENT COMPOSITE FILAMENTS CONSISTING OFF POLYESTERAND POLYAMIDE AND (B) POLYESTER MONOFILAMENTS, SAID POLYAMIDE BEINGSELECTED FROM THE GROUP CONSISTING OF POLYHEXAMTHYLENE ADIPAMIDE,POLYCAPROAMIDE AND COPOLYAMIDES THEREOF, SAID POLYESTER BEING SELECTEDFROM THE GROUP CONSISTING OF POLYETHYELENE TERPHTHALATE AND COPOLYESTERSTHEREOF WHICH COMPRISES SIMULTANEOUSLY AND SEPARATELY SPINNING THROUGH ACOMMON SPINNERET (1) MONOFILAMENTS OF POLYESTER HAVING A DENIER OF MORETHAN 2 TO FORM A COMPONENT (B) AND (2) COMPOSITE FILAMENTS OF POLYESTERAND POLYAMIDE IN WHICH THE POLYESTER OF EACH COMPOSITE FILAMENT ISDIVIDED INTO AT LEAST THREE SEPARATE SEGMENTS BY THIN INTERSECTINGPOLYAMIDE LAYER HAVING A SUBSTANTIALLY UNIFORM THICKNESS THROUGHOUTTHEIR LENGTH AND WHICH EXTEND RADIALLY AND DIVEREGE IN A DIRETION AWAYFROM THEIR INTERSECTION TOWARD THE PERIPHERY OF SAID COMPOSITE FILAMENT,SAID POLYESTER SEGMENTS HAVING A DENIER OF LESS THAN 1, SAID COMPOSITEFILAMENTS BEING FROM 40 TO 70 PERCENT BY WEIGHT BASED ON THE SUM OF THEWEIGHTS OF SAID MONOFILAMENTS AND COMPOSITE FILAMENTS, SAID POLYAMIDBEING LESS THAN 40 PERCENT BY WEIGHT BASED ON THE WEIGHT OF SAIDCOMPOSITE FILAMENTS AND SAID POLYAMIDE BEING LESS THAN 30 PERCENT BYWEIGHT BASED ON THE SUM OF THE WEIGHTS OF SAID MONOFILAMENTS ANDCOMPOSITE FILAMENTS, COMBINING THE MONOFILAMENTS AND COMPOSITEFILAMENTS, DRAWING THE COMBINED FILAMENTS AND THEN FALSE TWISTING THECOMBINED FILAMENTS TO FIBRILLATE SAID COMPOSITE FILAMENTS WHEREBY TOFORM A YARN IN WHICH THE FIBRILLATED SEGMENTS OF SAID COMPOSITEFILAMENTS AND SAID POLYESTERE MONOFILAMENTS ARE ENTANGLED AND AREHOMOGENEOUSLY DISPERSED.
 2. A method as claimed in claim 1, wherein saidpolyamide in the total mixed filaments is less than 25 percent byweight.
 3. A method as claimed in claim 1, wherein said polyamide in thecomposite filaments is less than 30 percent by weight.
 4. A method asclaimed in claim 1, wherein said polyamide in the composite filament isof X-shaped form, Y-shaped form or six-arm radial-shaped.
 5. A method asclaimed in claim 1, wherein the polyester segments in the compositefilament are is less than 0.7 denier.
 6. A method as claimed in claim 1,wherein the polyester monofilament is 3-10 deniers.
 7. A method asclaimed in claim 1, wherein the polyester is polyethylene terephthalate.8. A method as claimed in claim 1, wherein the polyamide ispolyhexamethylene adipamide.
 9. A method as claimed in claim 1, whereinthe polyamide is epsilon -polycaproamide.
 10. A method according toclaim 1, in which the feed ratio of polyester to polyamide fed to saidspinneret is 7/1 or less and the conjugation ratio of polyester topolyamide in said composite filament is 3/1 or less.